However it seems as though some of the copies of the above books that Imam Nawawi (rahimahullah) had, have the words wa la hawla. Imam Nawawi (rahimahullah) has recorded this hadith in his Riyadus Salihin and Al Azkar with the words wa la hawla .

(Riyadus Salihin, Hadith: 88 and Al Azkar, Hadith: 57)

The ideal would be to read what is found in the primary hadith sources today. ie. la hawla andnot wa la hawla.